| MITACS | Mathematics of Information Technology and Complex systems | In English | → Computer science → Mathematics |
| MITSIM | Microscopic Traffic Simulator | In English | → Computer simulation → Transport and postal services |
| MITSIS | Massachussets Institute of Technology's Student Information System | In English | → Computer science → Knowledge management → Specialized or (poly)technical colleges |
| MKiDN | Ministerstwo Kultury i Dziedzictwa Narodowego (www.mk.gov.pl) | In Polish | → Central administration → Civilization, culture, progress |
| MLC | Mobile Launcher Computer | In English | → Hardware → Spaceflight engineering, astronautics |
| MLE | Maximum Likelihood Estimation | In French | → Computer science → Mathematics |
| MLear | Machine Learning | In English | → Serial publications, periodicals → Artificial intelligence |
| MLP | Machine Language Program | In English | → Programming languages |
| MLUG | Montreal Linux Users Group | In English | → Organizations and associations → Operating systems |
| MM | Main Memory | In English | → Memories |
| MMACS | Maintenance Management and Control System | In English | → Maintenance and logistics |
| MMAS | Material Management and Accounting System | In English | → Maintenance and logistics |
| MMAS | Mechanized Material Accountability System | In English | → Maintenance and logistics → Mechanical engineering |
| MMC | Master Microprocessor Control | In English | → Hardware → Electronics |
| MMC | Mission Management Center | In English | → Management |
| MMCC | Mission Management and Control Centre | In English | → Management |
| MMD | MSC Maintenance Depot | In English | → Maintenance and logistics |
| MMD | Mobile Maintenance Depot | In English | → Maintenance and logistics |
| MMDB | Master Measurement Data Base | In English | → Data |
| MMDF | Mission Model Data File | In English | → Data |
| MMDS | Maintenance Management Data System | In English | → Data → Maintenance and logistics |
| MMES | Mikroszámítógép-mikroelektronikai értelmező szótár | In Hungarian | → Computer science → Dictionaries |
| MMG | Multimedia Management Group | In English | → Management → Telecommunications |
| MMI | Man-Machine Interaction = MDI | Människa-datorinteraktion | In Swedish = CHI | Computer-Human Interaction | In English = IHM | Interface Homme-Machine | In French |
In English | → Human-computer interaction |
| MMI | Man-Machine Interface | In English | → Human-computer interaction |
| MMIDS | Man-Machine Interface Development Station | In English | → Human-computer interaction |
| MMIE | Maximum Mutual Information Estimation | In English | → Computer science → Linguistics |
| MMIP | Mass Memory Integration Plan | In English | → Memories |
| MMO | Massively Multiplayer Online | In English | → Software → Networks, communication |
| MMORPG | Massively Multiplayer Online Role Playing Game | In English | → Software |
| MMP | Mission Management Plan | In English | → Management |
| MMPO | Mission Management and Planning Office | In English | → Management |
| MMS | Module Management System | In English | → Management |
| MMT | Mission Management Team | In English | → Management |
| MMT | Mass Memory Test | In English | → Memories |
| MMT | Médecins Maîtres-Toile | In French | → Networks, communication → Organizations and associations → Medicine |
| MMU | Mass Memory Unit | In English | → Memories |
| MMUS | Mass Memory Unit Simulator | In English | → Memories |
| MN | Main Bus | In English | → Computer science |
| MNPQ | Messen, Normen, Prüfen und Qualitätssicherung | In German | → Quality management → Engineering, technology |
| MO | Maintenance Organization | In English | → Maintenance and logistics |
| MOC | Mission Operations Computer | In English | → Hardware |
| MOCF | Mission Operations Computational Facility | In English | → Computer science |
| MOCN | Machine-Outil à Commande Numérique | In French | → Computer-based techniques → Mechanical engineering |
| MOLAP | Multidimensional On Line Analytical Processing | In English | → Knowledge management → Data |
| MOM | MiddleWare Orienté Message | In French | → Computer science |
| MOM | Mission Operations Manager | In English | → Management |
| MOM | Message Oriented Middleware | In English | → Software |
| MOP | Mission Operations Processor | In English | → Hardware |
| MORT | Management Oversight and Risk Tree | In English | → Management |
| MOSS | Microsoft Office SharePoint Server | In English | → Networks, communication → Knowledge management |
| MPAR | Maintainability Problem and Assessment Report | In English | → Maintenance and logistics |
| MPB | Maintenance Parts Breakdown | In English | → Maintenance and logistics |
| MPC | Material Procurement Cost | In English | → Maintenance and logistics → Prices |
| MPC | Memory Protection Check | In English | → Memories |
| MPD | Management Position Description | In English | → Management |
| MPEG | Moving Picture Experts Group | In English | → Graphical processing → Image processing → Cinema, movies |
| MPI | Message Passing Interface | In English | → Human-computer interaction |
| MPI | Message Parsing Interface | In English | → Human-computer interaction |
| MPII | Max-Planck-Institut Informatik | In German | → Computer science |
| MPL | Materials and Process List | In English | → Maintenance and logistics |
| MPL | Mechanical Parts List | In English | → Maintenance and logistics → Mechanical engineering |
| MPL | Master Program Library | In English | → Software |
| MPL | Maintenance Parts List | In English | → Maintenance and logistics |
| MPLS | Multi Protocol Label Switching | In English | → Networks, communication → Food technology |
| MPMP | Mechanical Parts, Material & Process(es) | In English | → Maintenance and logistics → Mechanical engineering |
| MPP | Material Processing Procedure | In English | → Maintenance and logistics |
| MPR | Maintainability Problem Report | In English | → Maintenance and logistics |
| MPR | Malfunction Problem Record | In English | → Management |
| MPR | Monthly Program Review | In English | → Management |
| MPR | Managerial and Professionnal Staff Association | In English | → Associations → Labour, labour economics → Management |
| MPS | Master Production Schedule | In English | → Management |
| MPS | Master Program Schedule | In English | → Management |
| MR | Management Review | In English | → Management |
| MR | Material Review | In English | → Maintenance and logistics |
| MR | Material Request | In English | → Maintenance and logistics |
| MR | Maintenance and Refurbishment | In English | → Maintenance and logistics |
| MRA | Mission Requirements and Allocation | In English | → Management |
| MRA | Mission Requirements Analysis | In English | → Management |
| MRAM | Magnetoresistive Random Access Memory | In English | → Memories |
| MRAM | Magnetic Random Access Memory | In English | → Memories |
| MRB | Material Review Board | In English | → Maintenance and logistics |
| MRBT | Maintenance Réseaux-Bureautique-Télématique | In French | → Computer science → Telecommunications |
| MRD | Material Review Disposition | In English | → Maintenance and logistics |
| MRD | Mission Requirements Document | In English | → Management |
| MRD | Mission Requirements Definition | In English | → Management |
| MRDA | Mission Requirements Definition and Analysis | In English | → Management |
| MRDB | Mission Requirements Data Base | In English | → Management |
| MRDR | Material Review Disposition Record | In English | → Image processing |
| MRDR | Mission Requirements Data Base Rockwell | In English | → Knowledge management |
| MRE | Material Review Engineering | In English | → Maintenance and logistics |
| MRF | Maintenance Responsibility File | In English | → Maintenance and logistics |
| MRI | Mixed Reality Interface | In English | → Human-computer interaction |
| MRIM | MOD/MOC Reconfiguration Interface Manager | In English | → Human-computer interaction |
| MRL | Material Requirements List | In English | → Maintenance and logistics |
| MRLUG | Montreal Regional Linux Users Group | In English | → Organizations and associations → Operating systems |
| MRM | Mission Requirements Matrix | In English | → Knowledge management |
| MRO | Maintenance Repair and Operation | In English | → Maintenance and logistics |
| MRO | Material Release Order | In English | → Maintenance and logistics |
| MRO | Memory Read-Out | In English | → Memories |
| MRO | Maintenance, Repair and Overhaul | In English | → Maintenance and logistics |
| MRP | Material Review Process | In English | → Maintenance and logistics |
| MRP | Material Requirements Planning | In English | → Maintenance and logistics |
| MRP | Manufacturing Resource Planning | In English | → Maintenance and logistics |
| MRP | Mission Reference Plane | In English | → Management |
| MRR | Manufacturing Readiness Review | In English | → Maintenance and logistics → Engineering, technology |
| MRR | Mission Requirements Review | In English | → Management |
| MRR | Mission Readiness Review | In English | → Management |
| MRS | Management Review System | In English | → Management |
| MRS | Master Repair Schedule | In English | → Maintenance and logistics |
| MRTS | Modification And Repair Tracking System | In English | → Maintenance and logistics |
| MRTS | Modification Recycle Tracking System | In English | → Maintenance and logistics |
| MRTS | Material Requirements Tracking System | In English | → Maintenance and logistics |
| MRWG | Mission Requirements Working Group | In English | → Management |
| MRZ | Medizinisches Rechenzentrum | In German | → Computer science → Medicine |
| MS | Material Specification | In English | → Maintenance and logistics → 620 |
| MS-DOS | Microsoft Disk Operating System | In English | → Operating systems |
| MSA | Material Service Area | In English | → Maintenance and logistics |
| MSA | Master Schedule Authorization | In English | → Management |
| MSA | Material Subcontract Administrator | In English | → Maintenance and logistics |
| MSA | Malta Standards Authority | In English | → Organizations and associations → Standardization |
| MSAD | Materials Summary Acceptance Document | In English | → Maintenance and logistics |
| MSB | Most Significant Bit | In English | → Computer science |
| MSC | Master Schedule Chart | In English | → Management |
| MSC | Materials Service Center | In English | → Maintenance and logistics |
| MSCB | Manufacturing Status Control Board | In English | → Maintenance and logistics → Engineering, technology |
| MSCL | Measurement Standards and Calibration Laboratory | In English | → Research institutes → Standardization |
| MSD | Mission Support Directorate | In English | → Management |
| MSDNAA | Microsoft Developer Network Academic Alliance | In English | → Organizations and associations → Computer science |
| MSDOS | Mass Storage Digital Operating System | In English | → Operating systems |
| MSDOS | Microsoft Disk Operating System | In English | → Operating systems |
| MSDS | Materials Safety Data Sheet | In English | → Maintenance and logistics |
| MSDT | Multiple Shuttle Data Tape | In English | → Data → Spaceflight engineering, astronautics |
| MSE | Maintenance Support Equipment | In English | → Maintenance and logistics |
| MSF | Maintenance Source File | In English | → Maintenance and logistics |
| MSG | Maintenance Study Group | In English | → Maintenance and logistics |
| MSG | Maintenance Steering Group | In English | → Maintenance and logistics |
| MSG | Mobile Standards Group | In English | → Standardization → Telecommunications |
| MSI | Maintenance-Significant Item | In English | → Maintenance and logistics |
| MSIS | Man-Systems Integration Standards | In English | → Standardization → Human-computer interaction |
| MSK | Mary Shift Keying | In English | → Human-computer interaction |
| MSK | Manual Select Keyboard | In English | → Hardware |
| MSKLC | Microsoft Keyboard Layout Creator | In English | → Operating systems |
| MSL | Master System Library | In English | → Computer science |
| MSMA | Maintenance des Systèmes Mécaniques Automatisés | In French | → Maintenance and logistics → Mechanical engineering |
| MSS | Manufacturers' Standardization Society | In English | → Organizations and associations → Standardization → Engineering, technology |
| MSS | Multisystem Software | In English | → Software |
| MSS | Maintenance Status System | In English | → Maintenance and logistics |
| MST | Mountain Standard Time | In English | → Standardization |
| MTA | Maintenance Task Analysis | In English | → Maintenance and logistics |
| MTB | Materials Testing Branch | In English | → Maintenance and logistics → 620 |
| MTBCF | Mean Time Between Critical Failures | In English | → Maintenance and logistics |
| MTBF | Mean Time Between Failures | In English | → Maintenance and logistics |
| MTBF | Mean Time Between Failure | In English | → Computer science |
| MTBM | Mean Time Between Maintenance | In English | → Maintenance and logistics |
| MTBMA | Mean Time Between Maintenance Action | In English | → Maintenance and logistics |
| MTBR | Mean Time Between Replacement | In English | → Maintenance and logistics |
| MTBR | Mean Time Between Removal | In English | → Maintenance and logistics |
| MTC | Microsoft Technology Center | In English | → Computer science |
| MTE | Maintenance Test Equipment | In English | → Maintenance and logistics |
| MTEC | Maintenance Test Equipment Catalog | In English | → Maintenance and logistics |
| MTEE | Maintenance Test Equipment, Electrical | In English | → Maintenance and logistics → Electrical engineering |
| MTEF | Maintenance Test Equipment, Fluid | In English | → Maintenance and logistics |
| MTEM | Maintenance Test Equipment Module | In English | → Maintenance and logistics |
| MTEM | Maintenance Test Equipment, Mechanical | In English | → Maintenance and logistics → Mechanical engineering |
| MTEO | Maintenance Test Equipment, Optical | In English | → Maintenance and logistics |
| MTG | Music Technology Group | In English | → Computer-based techniques → Music |
| MTJ | Mobile Tools for Java | In English | → Software |
| mTLD | mobile Top Level Domain | In English | → Networks, communication → Telecommunications |
| MTM | Multiterminal Monitor | In English | → Human-computer interaction |
| MUMPS | Massachusetts General Hospital Utility Multi-Programming System | In English | → Programming languages → Medicine |
| MUNCI | Mouvement pour une Union Nationale des Consultants en Informatique | In French | → Computer science → Organizations and associations → Consulting |
| MURI | Multi-disciplinary Research Initiative | In English | → Research policy → Mathematics and natural sciences |
| MUS | Mission-Unique Software | In English | → Software |
| MUSIC | Multiple Signal Classification | In English | → Networks, communication → Telecommunications |
| MVD | Map and Visual Display | In English | → Human-computer interaction |
| MVS | Multiple Virtual Storage | In English | → Memories |
| MWD | Material Withdrawal Document | In English | → Maintenance and logistics |
| MWG | Maintainability Working Group | In English | → Maintenance and logistics |
| MWOR | Maintenance Work Order Request | In English | → Maintenance and logistics |
| MWPR | Monthly Work Package Report | In English | → Management |
| MXML | Macromedia Flex Markup Language | In English | → Programming languages |
| MYTA | Maintainability Task Analysis | In English | → Maintenance and logistics |
| MYVAL | Maintainability Evaluation | In English | → Maintenance and logistics |
| NA | Network Aspects | In English | → Networks, communication |
| NABS | Nomenclature pour l'Analyse et la comparaison des Budgets et des programmes Scientifiques | In French | → Research policy |
| NAD | Network Adapter Device | In English | → Hardware → Networks, communication |
| NAF | Nazioarteko Alfabeto Fonetikoa = AFI | Alfabetul Fonetic Internaţional | In Romanian = LFE | Lizherenneg Fonetikel Etrebroadel | In Breton = МФА | Международната фонетична азбука | In Bulgarian = IPA | Internationales Phonetisches Alphabet | In Tosk = AFI | Alfabet fonètic internacional | In Catalan = IFA | Internacia Fonetika Alfabeto | In Esperanto = IPA | International Phonetic Alphabet | In English = ΔΦΑ | Διεθνές Φωνητικό Αλφάβητο | In Greek = IPA | Internationales Phonetisches Alphabet | In German = API | Alphabet Phonétique International | In French = AFI | Alfabeto Fonético Internacional | In Spanish = AFI | Alfabeto Fonético Internacional | In Galician = IPA | Internationalt Phonetescht Alphabet | In Letzeburgesh = AFI | Alfabeto Fonetico Internazionale | In Italian = МФА | Международный фонетический алфавит | In Russian = AFI | Alfabeto Fonético Internacional | In Portuguese = AFI | Alfabet fonetic internacionau | In Occitan = AFE | Alfabet Fonetike Eternåcionå | In Walloon = IFA | Internationoal Fonetisch Alfabet | In Vlaams = AFN | Alfabeti Fonetik Ndërkombëtar | In Albanian |
In Basque | → Writing systems |
| NAOMI | North American OpenMath Initiative | In English | → Computer science → Mathematics |
| NAPCTC | North American Policy Council for OSI (Open Systems Interconnection) Testing and Certification | In English | → Computer science |
| NAR | Numerical Analysis Research | In English | → Computer-based techniques |
| NAS | National Aircraft Standard | In English | → Standardization → Aeronautics, aircraft |
| NAS | Nonavionics Simulator | In English | → Computer simulation → Aeronautics, aircraft |
| NAS | Numerical Aerodynamic Simulation | In English | → Computer simulation → Aerodynamics |
| NAS | Network Attached Storage | In English | → Networks, communication → Knowledge management |
| NAUTILE | Noyau d'Aide à l'Usage, la Transmission et l'Installation des Logiciels libres sur l'Estuaire | In French | → Organizations and associations → Software |
| NBIC | Nanotechnology, Biotechnology, Information Technology and Cognitive Science | In English | → Computer science → Biotechnology → Engineering, technology |
| NBMA | Nonbroadcast Multiple Access Network | In English | → Networks, communication → Telecommunications |
| NBR | National Bureau of Asian Research | In English | → Research policy |
| NBS | National Bureau of Standards | In English | → Standardization |